斗鱼属鱼类亲缘关系的Cyt b基因序列和RAPD分析

采用mtDNA Cyt b基因序列分析和RAPD两种分子标记技术,研究了中国分布的叉尾斗鱼(Macropodus opercularis)、圆尾斗鱼(M.chinensis)和香港斗鱼(M.hongkongensis)以及越南的红鳍斗鱼(M.erythropterus)4种鱼类之间的亲缘关系.获得4种斗鱼14条Cyt b基因全序列(1 155 bp),结合GenBank中搜索到的近缘物种同源序列进行分析.从133条随机引物中筛选到36条引物,在优化的反应条件下,10个群体96个个体共扩增出清晰稳定的条带749条,构建矩阵进行分析和聚类.基于Cyt b全序列以邻接法和最小进化法构建的系统树及RAPD数据UPGMA聚类分析的结果都显示,香港斗鱼和红鳍斗鱼先聚为一分支,再与叉尾斗鱼聚类,圆尾斗鱼处于外缘.本研究结果反映了圆尾斗鱼与其他斗鱼的亲缘关系较远,种间遗传距离为0.184 5～0.225 3(Cyt b)和0.653 6～0.746 5(RAPD),两者为同一单系群中两个独立演化的自然类群;香港斗鱼与叉尾斗鱼间遗传分化明显,Cyt b碱基差异为11.00%,RAFD遗传距离达0.577 7,支持其为独立物种的观点,且香港斗鱼群体间遗传差异较大,Cyt b碱基差异为3.12%,RAPD遗传距离0.060 1;叉尾斗鱼群体间Nei's基因多样度和Shannon信息指数分别为0.058 2和0.086 9,而各群体内的数值分别为0.016 1～0.031 7和0.023 5～0.046 7,表明遗传差异主要来自群体间,并按分布流域分别聚类.     

基于COI和ND5序列的中国南部唇魚骨和间魚骨群体遗传结构

唇魚骨和间魚骨均为分布较广的初级淡水鱼类,是理想的亲缘地理研究材料;且两者形态特征较为相似,不易鉴别,故两者的分布记述和物种有效性存在争议.为了解我国南部唇魚骨和间魚骨的群体遗传结构并探讨两者的物种有效性,本研究对8条水系的唇魚骨和9条水系的间魚骨共130尾个体的COI和ND5基因序列片段进行了测定,并对这两个基因的组合序列(2151bp)进行了分析.结果表明:在130尾个体的COI和ND5基因组合序列中,共有196个核苷酸变异位点,共检测出50个单倍型,单倍型多样性为0.964,核苷酸多样性为0.019,遗传多样性较高.基于COI和ND5基因组合序列构建的NJ树显示,所有种群可分为两支,支系Ⅰ包含了韩江和九龙江的全部单倍型以及瓯江的部分单倍型,余下的单倍型组成了支系Ⅱ.两支系间的遗传距离为0.036,而唇魚骨与间魚骨之间的遗传距离为0.027.单倍型网络图表明,韩江、九龙江种群和其他水系种群分化较大;漠阳江种群由海南岛种群扩散而来;海南岛各种群及漠阳江种群的单倍型分支与珠江水系单倍型的分支之间的亲缘关系较近,与长江水系单倍型分支之间的亲缘关系则较远;湘江、桂江和柳江之间的亲缘关系较近.AMOVA分析结果显示,地理区之间的变异约占71.2%,地理区内种群间变异约占16.6%,种群内的变异占12.2%,表明其遗传分化主要来自地理区之间.错配分析及中性检验结果显示,全部种群、唇魚骨种群、间魚骨种群、支系Ⅰ和支系Ⅱ在历史上均没有发生过明显的扩张.     

基于线粒体Cyt b基因的中国南方唇鱼骨(Hermibarbus labeo)和间鱼骨(Hermibarbus medius)种群分化及亲缘地理研究

为了解中国南方唇鱼骨（Hermibarbus labeo）和间鱼骨（Hermibarbus medius）的种群分化、亲缘地理格局及物种有效性,作者对唇鱼骨8个水系及间鱼骨9个水系共148尾样本的Cyt b基因全序列进行了测定。在所有序列中,共有128个变异位点,共检测出了41个单倍型,单倍型多样性为0.954,核苷酸多样性为0.02153。基于Cyt b基因全序列构建的NJ树显示,中国南方的唇鱼骨与间鱼骨合聚为两大支,其中韩江和九龙江的全部唇鱼骨样本组成了Ⅰ支,而其他水系的唇鱼骨和间鱼骨样本则组成了Ⅱ支。两支系间的遗传距离为5.1%,而唇鱼骨和间鱼骨之间的遗传距离为3.2%。现有证据不支持间鱼骨与唇鱼骨达到种一级的分化。单倍型网络图显示,韩江、九龙江种群和其他水系的种群分化较大;海南岛三大水系种群和漠阳江种群的单倍型分支与代表珠江水系单倍型的分支之间的亲缘关系较近,与其他地理区间种群的亲缘关系则相对较远;西江可能为珠江水系、漠阳江水系和海南岛三大水系间鱼骨种群的扩散中心,其中一支往东向北江和东江扩散;另一支往南向海南岛扩散,海南岛三大水系种群尔后在冰期海退时向北扩散至漠阳江水系及珠江水系。AMOVA分析表明,唇鱼骨和间鱼骨地理区之间变异约占54.50%,地理区内种群间变异约占18.64%,种群内的变异占26.86%,这说明,唇鱼骨和间鱼骨种群Cyt b的遗传分化主要是来自地理区之间。错配分析及中性检验显示,全部种群、唇鱼骨种群、间鱼骨种群在历史上均没有发生过明显的扩张,两个mtDNA支系亦未发生过扩张,而海南岛的昌化江种群曾发生过种群扩张。     

基于线粒体Cyt b基因的中国南方唇(Hermibarbus labeo)和间(Hermibarbus medius)种群分化及亲缘地理研究

为了解中国南方唇(Hermibarbus labeo)和间(Hermibarbus medius)的种群分化、亲缘地理格局及物种有效性,作者对唇8个水系及间9个水系共148尾样本的Cyt b基因全序列进行了测定。在所有序列中,共有128个变异位点,共检测出了41个单倍型,单倍型多样性为0.954,核苷酸多样性为0.02153。基于Cyt b基因全序列构建的NJ树显示,中国南方的唇与间合聚为两大支,其中韩江和九龙江的全部唇样本组成了Ⅰ支,而其他水系的唇和间样本则组成了Ⅱ支。两支系间的遗传距离为5.1%,而唇和间之间的遗传距离为3.2%。现有证据不支持间与唇达到种一级的分化。单倍型网络图显示,韩江、九龙江种群和其他水系的种群分化较大;海南岛三大水系种群和漠阳江种群的单倍型分支与代表珠江水系单倍型的分支之间的亲缘关系较近,与其他地理区间种群的亲缘关系则相对较远;西江可能为珠江水系、漠阳江水系和海南岛三大水系间种群的扩散中心,其中一支往东向北江和东江扩散;另一支往南向海南岛扩散,海南岛三大水系种群尔后在冰期海退时向北扩散至漠阳江水系及珠江水系。AMOVA分析表明,唇和间地理区之间变异约占54.50%,地理区内种群间变异约占18.64%,种群内的变异占26.86%,这说明,唇和间种群Cyt b的遗传分化主要是来自地理区之间。错配分析及中性检验显示,全部种群、唇种群、间种群在历史上均没有发生过明显的扩张,两个mt DNA支系亦未发生过扩张,而海南岛的昌化江种群曾发生过种群扩张。     

艾氏管鼻蝠种群遗传结构初步研究及其分类探讨

艾氏管鼻蝠是2009 年发表的新种,其体型较小,外形与金管鼻蝠极其相似,本文以广东采集的艾氏管鼻蝠线粒体部分COI 序列片段为分子标记,对其种群遗传结构进行了初步分析,并与金管鼻蝠形态进行比较,对2个种的外形特征及分类地位进行了探讨。结果表明: (1) 本研究获得的艾氏管鼻蝠序列与BOLD 数据库中的“金管鼻蝠”序列聚为一支,遗传差异极小; (2)华南区域艾氏管鼻蝠并非单系,其种群遗传结构与种群地理分布模式不一致,贵州、广东与越南、老挝种群的亲缘关系较广西种群更近; (3)现有数据库及国内部分研究中鉴定的“金管鼻蝠”实际应为艾氏管鼻蝠。     

中国蒿属沙生地理替代种亲缘关系的RAPD分析

运用随机扩增多态性DNA技术对中国蒿属沙生地理替代种共23个地理种群的遗传差异进行了检测,15个引物共获得303个位点。根据遗传距离的聚类分析结果显示：每个种的不同种群均各自聚到一起,反映出种间存在着一定的遗传分化。23个种群被分为三大支,白沙蒿与准噶尔沙蒿为一支,表明两者有着很近的亲缘关系。黑沙蒿、褐沙蒿、差不嘎蒿聚为一支,且遗传距离很小,反映出三个种有着最近的亲缘关系,乌丹蒿则自成一支,与其它种亲缘关系较远。结合形态与分布,提出褐沙蒿应作为黑沙蒿的地理亚种。     

日本稻蝗、中华稻蝗和赤胫伪稻蝗地理种群的RAPD遗传分化研究

运用10个RAPD引物对日本稻蝗(Oxya japonica)、中华稻蝗(Oxya chinensis)和赤胫伪稻蝗(Pseudoxya diminuta)的种群遗传分化进行分析。10个随机引物共产生135条带,扩增谱带具有明显的属、种间多态性。Shannon信息指数表明中华稻蝗遗传多样性水平较高(2．693),日本稻蝗次之(2.319),赤胫伪稻蝗最低(1．042)。中华稻蝗和日本稻蝗的不同地理居群出现遗传分化,由Shannon信息指数估算的种群间遗传分化系数分别为20．7％,42．4％。用UPGMA和NJ法对Nei’s遗传距离作聚类分析,构建分子系统树。系统树显示：同一种群的不同个体优先相聚,而后,同一种的不同种群依次相聚;日本稻蝗广西南宁种群和广东广州种群首先聚为一支,陕西西安种群和浙江杭州种群聚为另一支,两支相聚后与中华稻蝗聚在一起,最后与赤胫伪稻蝗相聚。聚类结果表明：不同地域日本稻蝗亲缘关系的远近与地理距离呈现一定的相关趋势,日本稻蝗与中华稻蝗亲缘关系较近,Nei’S遗传距离平均为0．142,而赤胫伪稻蝗与它们关系较远,Nei’s遗传距离平均为0．451。聚类图所显示的物种间亲缘关系的远近程度与形态分类学和细胞分类学结果相一致。     

葱属12种植物的RAPD分析

采用随机引物扩增多态DNA技术对葱属部分植物进行了种间亲缘关系的研究。结果说明12种材料之间存在丰富的多态性,遗传距离变幅在0.2500-0.7887之间,聚类分析说明蒙古韭,山韭,野韭,韭菜（栽培韭）,野生韭菜,矮韭亲缘关系较近,聚为一支,其中韭菜与野生韭菜亲缘关系最近。天蒜,薤白,蒜聚为一支,葱,洋葱,红葱聚为一支,其中葱与洋葱,红葱的遗传分化较大。     

蒙古沙拐枣种群形态和同工酶变异的比较研究

调查和测定了中国西北荒漠地区的蒙古沙拐枣(Calligomum mongolicum Turcz)5个种群的形态学指标,应用方差分析(MANOVA)、主成分分析(PCA)和聚类分析,对种群间及种群内的形态性状进行研究。结果表明,种群间的形态变异差异显著。植株高度、种子刺毛长度和种子重量指标具有较强的形态差异性分析意义。形态差异(欧氏距离)与种群间基因流动(地理距离)间没有发现相关关系。聚类分析结果表明,种群M1与M2亲缘关系最近,种群M5与其他种群的亲缘关系相对较远;采用垂直板聚丙烯酰胺电泳技术对5个种群的3个酶系统进行了遗传多样性分析,结果表明,种群M5与其他种群的遗传一致度稍低(0．8197～0．8902)以外,其余各种群遗传一致度较高(0．8480～0．9505),体现其亲缘关系较近。依据Nei的遗传距离进行聚类,结果与形态聚类结果有一定的相似性。     

中国境内不同地理型东方蜜蜂遗传多样性的AFLP分析

利用22对AFLP引物组合对我国9个省市的11个东方蜜蜂种群和1个西方蜜蜂种群的39个个体基因组DNA的遗传变异进行了研究;根据AFLP分析结果,采用GeneScan3.0软件、群体遗传数据分析包（Hickory v1.0.4） 和群体遗传变异分析程序（AFLP-SURV 1.0）,分别计算了39个个体间的遗传相似系数和各蜜蜂种群的Nei's遗传距离、Reynolds遗传距离和成对的固定指数F_st,并构建了各自的UPGMA聚类关系图。结果表明：AFLP标记具有很高的多态检测效率,适合于蜜蜂种群遗传多样性分析和品种鉴定。蜜蜂种间的遗传分化明显,亲缘关系较远。中国境内不同地理型东方蜜蜂群体间存在着广泛的遗传变异。UPMGA聚类关系图显示,海南东方蜜蜂由于长期的海岛隔离,已经形成了一个独特的类群,支持了通过形态学认定的海南东方蜜蜂为东方蜜蜂的一个新亚种。     

Effects of MULTIFOLIATE-PINNA, AFILA, TENDRIL-LESS and UNIFOLIATA genes on leafblade architecture in Pisum sativum

In order to dissect the genetic regulation of leafblade morphogenesis, 16 genotypes of pea, constructed by combining the wild-type and mutant alleles of MFP, AF, TL and UNI genes, were quantitatively phenotyped. The morphological features of the three domains of leafblades of four genotypes, unknown earlier, were described. All the genotypes were found to differ in leafblade morphology. It was evident that MFP and TL functions acted as repressor of pinna ramification, in the distal domain. These functions, with and without interaction with UNI, also repressed the ramification of proximal pinnae in the absence of AF function. The expression of MFP and TL required UNI function. AF function was found to control leafblade architecture multifariously. The earlier identified role of AF as a repressor of UNI in the proximal domain was confirmed. Negative control of AF on the UNI-dependent pinna ramification in the distal domain was revealed. It was found that AF establishes a boundary between proximal and distal domains and activates formation of leaflet pinnae in the proximal domain.     

Presence of Rhizobium Etli bv . Phaseoli and Rhizobium Gallicum bv . Gallicum in Egyptian Soils

Seven bean rhizobial strains EBRI 2, 3, 21, 24, 26, 27 and 29 identified as Rhizobium etli, and EBRI 32 identified as Rhizobium gallicum, isolated from Egyptian soils and which nodulated Phaseolus vulgaris efficiently, were subjected to hybridization with a nifH probe in order to estimate the copy number of this gene. Seven strains (EBRI 2, 3, 21, 24, 26, 27 and 29) which were only able to nodulate Phaseolus vulgaris, contained three copies of the nifH gene, consistent with their identification as Rhizobium etli bv. phaseoli. Only one strain (EBRI 32) which nodulated both Phaseolus vulgaris and Leucaena leucocephala, had one copy of nifH gene. This confirmed the classification of this strain as Rhizobium gallicum bv. gallicum.     

Characterisation of cell wall polysaccharides, arabinogalactans-proteins (AGPs) and phenolics of Cola nitida, Cola acuminata and Garcinia kola seeds

Many Cola plant species are endemic to West and Central Africa. Cola acuminata and Cola nitida are used as masticatory when fresh, while the dried nuts are used for beverages and pharmaceutical purposes in Europe and North America. Garcinia kola seeds, that serve as a substitute for the true kola nuts, are used in African traditional medicine for the treatment of various diseases, including colic, headache and liver cirrhosis. Seeds extracts of G. kola are also known for their anti-inflammatory, antimicrobial and antiviral properties. To gain information on the chemical properties of the kolas, we have isolated and analyzed cell wall polysaccharides, arabinogalactan-proteins and phenolic substances from the seeds of the three kola species. The sugar composition of cell wall material of C. acuminata, C. nitida and G. kola revealed that Gal (up to 30%), Ara, GalA and Glc as the predominant monosaccharides, representing approximately 90% by mol of the total hydrolysable sugar present in this material. In Ammonium oxalate cell wall fraction, GalA was found to be the major sugar present in all kola species. In the alkali-soluble fraction, there were significant differences in the level of Glc and Gal. The level of Glc was high in C. acuminata and C. nitida while the level of Gal and Xyl were high in C. nitida and G. cola. Isolation and quantification of arabinogalactan-proteins demonstrate that G. kola seeds contained four to eight times more of these proteoglycans than the seeds of the other two species. Finally, analysis of soluble phenolic substances shows that caffeine and catechin were largely represented in C. acumina and C. nitida seeds, with caffeine accounting for 50% of all soluble phenolics. These findings indicate that the three Kola seeds are highly enriched in pectins and proteoglycans and that C. acuminata and C. nitida can be used as a possible source of caffeine and catechin.     

Comparative study of Bifidobacteriumanimalis, Escherichiacoli, Lactobacilluscasei and Saccharomycesboulardii probiotic properties

The present work investigates some probiotic properties of four different microorganisms (Bifidobacterium animalis var. lactis BB-12, Escherichia coli EMO, Lactobacillus casei and Saccharomyces boulardii). In vitro and in vivo tests were carried out to compare cell wall hydrophobicity, production of antagonistic substances, survival capacity in the gastrointestinal tract of germ-free mice without pathological consequence, and immune modulation by stimulation of Küpffer cells, intestinal sIgA and IL-10 levels. In vitro antagonism against pathogenic bacteria and yeast was only observed for the probiotic bacteria B. animalis and L. casei. The hydrophobic property of the cell wall was higher for B. animalis and E. coli EMO, and this property could be responsible for a better ability to colonize the gastrointestinal tract of germ-free mice. Higher levels of sIgA were observed mainly for S. boulardii, followed by E. coli EMO and B. animalis, and only S. boulardii induced a significant higher level of IL-10. In conclusion, for a probiotic use, S. boulardii presented better characteristics in terms of immunomodulation, and B. animalis and L. casei for antagonistic substance production. The knowledge of the different probiotic properties could be used to choice the better microorganism depending on the therapeutic or prophylactic application.     

Prosthecium species with Stegonsporium anamorphs on Acer

Data from microscopic morphology, single-spore cultures, and DNA analyses of teleomorphs and anamorphs support the recognition of five species of Prosthecium with Stegonsporium anamorphs on Acer: P. acerinum sp. nov., the teleomorph of S. acerinum; P. acerophilum comb. nov., formerly known as Dictyoporthe acerophila; P. galeatum comb. nov., originally described as Massaria galeata; P. opalus sp. nov.; and P. pyriforme sp. nov., the teleomorph of S. pyriforme s. str. The morphology of both type specimens and freshly collected material was investigated. The teleomorphs have brown ellipsoidal ascospores with five distosepta and often a longitudinal distoseptum. The anamorphs of all species described here belong to Stegonsporium; their connection to the Prosthecium teleomorphs was demonstrated by morphology and DNA sequences of single spore cultures derived from both ascospores and conidia. The anamorphs and teleomorphs of all five Prosthecium species are described and illustrated by LM images, and a key to these species is provided. As perceived from this work, S. pyriforme is restricted to Europe and does not occur in North America, whereas S. acerinum is restricted to North America, not found in Europe. The host associations given in the literature are revised and evidence is provided that only A. opalus, A. pseudoplatanus, and A. saccharum are confirmed hosts of Prosthecium with Stegonsporium anamorphs. Molecular phylogenetic analyses of tef1, ITS rDNA, and partial nuLSU rDNA sequences confirm that the species with Stegonsporium anamorphs are closely related to P. ellipsosporum, the generic type species. Stilbospora macrosperma is confirmed as the anamorph of P. ellipsosporum by DNA data of single spore isolates obtained from both ascospores and conidia.     

铜绿假单胞菌对青霉素类抗生素异质性耐药研究

【背景】铜绿假单胞菌是临床上常见的条件致病菌,其异质性耐药的发生常导致临床治疗失败。【目的】研究铜绿假单胞菌对青霉素类抗生素的异质性耐药情况,为相关临床感染治疗提供一定的依据。【方法】收集临床分离的50株铜绿假单胞菌,采用纸片扩散法(diskdiffusion method)即Kirby-Bauer (K-B)法、菌落谱型分析(population analysis profile,PAP)法、生长实验以及传代稳定性实验探究铜绿假单胞菌的异质性耐药特征。【结果】K-B法初筛得到铜绿假单胞菌对哌拉西林(piperacillin,PIP)、哌拉西林/他唑巴坦(piperacillin/tazobactam,TZP)和替卡西林/克拉维酸(ticarcillin/clavulanic acid,TIM)的异质性耐药率分别为52%、52%和54%。PAP实验确认后有13株异质性耐药菌,其检出率占总实验菌株的26%。随机选取8株异质性耐药菌株,其耐药亚群的发生频率为7.3×10-7-1.2×10-5。通过无抗生素压力的生长实验发现,异质性耐药菌株PAS92、PAS57与其各自的3株最高PIP浓度平...     

Probing the Drosophila retinal determination gene network in Tribolium (II): The Pax6 genes eyeless and twin of eyeless

The Pax6 genes eyeless (ey) and twin of eyeless (toy) are upstream regulators in the retinal determination gene network (RDGN), which instructs the formation of the adult eye primordium in Drosophila. Most animals possess a singleton Pax6 ortholog, but the dependence of eye development on Pax6 is widely conserved. A rare exception is given by the larval eyes of Drosophila, which develop independently of ey and toy. To obtain insight into the origin of differential larval and adult eye regulation, we studied the function of toy and ey in the red flour beetle Tribolium castaneum. We find that single and combinatorial knockdown of toy and ey affect larval eye development strongly but adult eye development only mildly in this primitive hemimetabolous species. Compound eye-loss, however, was provoked when ey and toy were RNAi-silenced in combination with the early retinal gene dachshund (dac). We propose that these data reflect a role of Pax6 during regional specification in the developing head and that the subsequent maintenance and growth of the adult eye primordium is regulated partly by redundant and partly by specific functions of toy, ey and dac in Tribolium. The results from embryonic knockdown and comparative protein sequence analysis lead us further to conclude that Tribolium represents an ancestral state of redundant control by ey and toy.     

转Cry1Ac/1Ab基因棉花对异色瓢虫生长发育及其捕食功能的影响

【目的】为探究转Cry1Ac/1Ab基因棉花对异色瓢虫生长发育及其捕食功能的影响。【方法】以转Cry1Ac/1Ab基因棉与其亲本常规棉为实验材料,利用取食不同棉花品种叶片的棉铃虫饲喂异色瓢虫幼虫。【结果】与常规亲本棉相比,取食饲喂转基因棉花叶片的初孵棉铃虫幼虫的异色瓢虫幼虫从1龄发育至化蛹期时间延长0.77 d,但差异不显著;除1龄幼虫体重增加(0.0773 mg)外,其余各龄期幼虫体重均有所下降,但差异均不显著;异色瓢虫1、2、3、4龄幼虫对初孵棉铃虫捕食量均随棉铃虫密度的增加而增加,捕食功能反应均符合HollingⅡ圆盘方程。【结论】转Cry1Ac/1Ab基因棉花对异色瓢虫生长发育无显著影响,饲喂取食转Cry1Ac/1Ab基因棉花的棉铃虫对异色瓢虫捕食功能无显著差异。